ktvu's patti lee caught up with some that are saying the technology is missing the mark. >> reporter: we sat in on a mandatory treatment session for men arrested while driving under the influence. some are repeat offenders. >> today i introduce senate bill 55. >> reporter: state senator jerry hill introduced a bill that would require drivers convicted of a second dui offense to install an ignition interlock device or iid on their car for one year. the iid would prevent the car from starting. if there's alcohol on the drive's breath. >> we tried increasing fines, we've tried to revoke licenses to deter those chronic offenders but we need to do more to save lives. >> reporter: according to the most recent chp statistics drunk driving killed 1,200 californians in 2009, for those arrested of driving under the influence near 20% are second offenders. >> a lot of time these poor judgment calls result in very tragic events. >> reporter: paul chang oversees the treatment of thousands of people arrested while driving drunk. he says the bill is well intentioned but practical. >> the pure fact t